Ah, the Hellgrammite—nasty little critter, but man, do fish love ‘em. If you’ve ever flipped a rock in a fast-moving stream and seen one of those segmented, leggy monsters scuttling away, you know why this fly slays.

Tying it? Keep it simple. I stick to long shank hooks, size 4 to 8—personally, I’ve hammered smallmouth on a 6 in stained water. Lead wire underbody for weight (and to get that killer segmented look), then hit it with black or dark brown chenille. Some folks go crazy with the dubbing, but less is more here. Legs? Rubber. Black or brown, doesn’t matter much—just keep ‘em sparse. Saw a guy once tie one with enough legs to make a tarantula jealous. Fish ignored it. Coincidence? Nah.

What’s it mimic? Well, the Dobsonfly larva, obviously—but forget the textbook description. These things are like steak dinners for fish. Big, meaty, and dumb enough to get swept into the current. Smallies, trout, even bass’ll choke ‘em down. Once watched a smallmouth inhale one so hard it practically gagged. Wish I’d filmed it.

Where to fish it? Anywhere with rocks and current. Hellgrammites don’t exactly swim—they tumble and crawl. So get that fly down deep, bounce it off the bottom like the real deal.

Madison River? Killer there. But honestly, any rocky stretch with a decent flow’ll do. Just don’t overthink it. Cast, let it sink, twitch it along. Works. Every. Time.

Oh, and pro tip: if you’re not snagging occasionally, you’re not deep enough. Trust me.